Apparatus for making bulged articles



June 1963 D. PECCERILL 3,094,091

APPARATUS. FOR MAKING BULGED ARTICLES Filed D80. 22, 1959 3 Sheets-Sheet l ATTORNEY 5 June 18, 1963 VD. PECCERILL APPARATUS- FOR MAKING BULGED ARTICLES 5 Sheets-Sheet 2 Filed Dec. 22, 1959 INVENTOR BY g7 ATTORNEYS June 18, 1963 D. PECCERILL APPARATUS FOR MAKING BULGED ARTICLES 3 Sheets-Sheet 3 Filed D60. 22, 1959 INVENTOR ATTORNEYS United States Patent 3,094,091 APPARATUS FOR MAKING BULGED ARTICLES Donald Peccerill, 37 Susquehanna Ave., West Haven, Conn. Filed Dec. 22, 1959, Ser. No. 861,303 2 Claims. (Cl. 113-44) This invention relates to an apparatus for making bulged articles and more particularly the making of such articles from a sheet metal blank. While, as illustrated, the ap paratus is applied to such articles as hollow door knobs, it will be understood that the invention is applicable to the manufacture of other bulged sheet metal articles as well.

As illustrated the process is carried out upon a machine generally known as an eyelet machine which is provided with a plurality of plungers reciprocably mounted in a frame, which plungers carry working tools which cooperate wtih dies carried upon a die bed on the machine so that there is provided a plurality of work stations and the work done upon the blank is performed in a plurality of steps, one at each station, the workpiece or blank being progressively transferred from one station to the next. Such machines are also used in some instances for cupping and drawing operations as is the case with a multiple press, and in the present instance a plurality of operations are performed on the blank in order that the flat sheet metal blank be cupped and then drawn prior to the bulging operation. The bulging operation is performed at one station in the machine, and it is this station with which the invention is particularly concerned and in which the novel method is carried out.

In the operation an upper and a lower die are provided between which the work is disposed, these dies being relatively movable so that during the operation they may be brought together to snugly enclose the work. At the same time that the dies are brought together, a plunger or ram is moved toward the work, this plunger carrying a bag or container filled with liquid, which container is inserted into the hollow or cupped workpiece and continued movement of the plunger after the dies are closed serves to exert pressure upon the liquid in the bag or container to cause it to expand and thereby expand the walls of the workpiece into close contact with the die to form the finished article.

One object of the invention is to provide a novel apparatus of making bulged sheet metal articles such as hollow door knobs, for example, from a sheet metal blank.

Still another object of the invention is to provide a new and improved apparatus for making hollow bulged articles such as door knobs wherein a cupped blank is expanded by hydraulic pressure created within a container inserted in a cupped blank, this container being carried by a plunger or ram of such construction that the liquid will be trapped in the plunger and bag and may, therefore, be used in a continuous process without necessity for employing a new supply of liquid at each operation.

A still further object of the invention is to provide an apparatus for bulging cup-shaped sheet metal blanks wherein a pair of cooperating dies are provided, one movable with respect to the other, the relative movement of the dies being effected by novel means.

To these and other ends the invention consists in the novel features and combinations of parts to be hereinafter described and claimed.

In the accompanying drawings:

FIG. 1 is a front elevational view of a portion of an eyelet or similar machine adapted for carrying out my improved method;

FIG. 2 is a sectional view on line 2--2 of FIG. 1;

FIG. 3 is an enlarged sectional view on line 33 of 3,094,091 Patented June 18, 1963 FIG. 1 showing the tools employed at the bulging station in the machine;

FIG. 4 is a sectional view on line 44 of FIG. 3;

FIG. 5 is a horizontal sectional view on line 55 of FIG. 3;

FIG. 6 is an enlarged sectional view taken on the same plane as FIG. 3 but showing the working dies in open position and the plunger in withdrawn or upper position;

FIG. 7 is an enlarged sectional view taken on the same plane as FIG. 4 but showing the position of the working tools at the beginning of a bulging operation;

' FIG. 8 is a sectional view of the sheet metal workpiece or blank from which the bulged article is made;

FIG. 9 is a sectional view of the sheet metal blank after a cupping operation;

FIG. 10 is a view of the cupped article after a reduced neck has been drawn thereon; and

FIG. 11 is a sectional View of the completed article after the final bulging operation has been performed.

To illustrate a preferred embodiment of the invention I have shown in FIG. 1 of the drawings an eyelet machine or multiple plunger press comprising a frame 10 having spaced transverse frame members 11 and 12. Slidably mounted in these frame members are a plurality of plungers 13, each of which is designed to carry tools at its lower end to cooperate with a working die structure mounted upon a die bed shown at 14, this die bed being mounted upon a lower transverse frame member 15.

The present invention is particularly concerned with the operation performed at the last station of the machine which is shown in the sectional view of FIG. 2 wherein a lifter rod 16 is slidably mounted in the transverse members 11 and 12. Secured to this lifter rod is an arm 17 which is also secured to the plunger 13. A second arm 18 is secured to the lifter rod in spaced relation to the arm 17, which arm is adapted to be engaged by a lifting cam 19 secured to a cam shaft 20 so as to lift the plunger 13 or move it vertically as shown in the drawings. The descent of the plunger is effected by means of a cam 2-1 also mounted upon the shaft 20 and engaging an antifriction roller 22 mounted at the upper end of the plunger 13.

As shown in FIG. 1, the shaft 20 may be rotated through a belt 25 driven from any suitable source of power. The parts of the apparatus thus far described are common to machines of this character and it will be understood that in a well-known manner, when the shaft 20 is rotated, the plunger 13 will be reciprocated by cam 19 acting on the lifter rod 16 and by action of the cam 21 on the cam follower roller 22.

As shown in FIG. 3 a nut 26 is threadedly secured to the lower end of the plunger 13, and secured to this nut by a screw 27 is a hollow piston 28 having in the upper portion thereof a bore 29 closed by a gland screw 30.

The piston or ram 28 is provided with an annular flange 31, and between this annular flange and a nut 32 are mounted a series of packing glands 33 to provide a seal between the piston and a cylinder 34 slidably carried by the piston. The cylinder comprises a hollow cup-shaped body closed at its lower end by the bottom member 35 and is movably attached to the ram by means of a cap 36 threaded upon the upper end of the cylinder and projecting over the upper end of the latter so as to engage the flange 31, as shown in FIG. 6. A compression spring 37 acting between the nut 26 and the cap 36 tends to urge the cylinder downwardly against the flange 31.

A container 38 (FIG. 6) is secured at the lower end of the plunger, this container being formed of flexible, elastic material such as rubber or the like and is a baglike member open at its upper end. At its upper end the container is flanged outwardly as shown at 39 and is held to the bottom 35 of the cylinder between two flanged sleeves 4t) and 41 by a nut or cap 42 threaded upon the lower end of the cylinder. An opening 43 in the bottom of the cylinder establishes communication between the latter and the bag or container 38 which by the above-described connection is sealed in watertight relation to the cylinder. In operation it will be understood that the cylinder 34 and bag or container 38 are filled with liquid such as water, for example, and movement of the piston relatively to the cylinder in a downward direction, as illustrated, will force the liquid in the cylinder into the container and effect expansion of the walls of the latter as will be more fully explained hereinafter.

Mounted in the die bed 14 is a lower die 44 provided in its upper face with a working die opening or cavity 45. Slidably mounted in the die 44 is a knock-out or ejecting rod 46, this rod, as shown in FIGS. 1 and 2, extending downwardly through the member 15 and being actuated by the cam 47 mounted on a cam shaft 48. This shaft may be driven by the countershaft 49 from the shaft 20 previously referred to. It will be understood rthat the working opening or cavity 45 in the die 44 will be of such configuration as to correspond with the shape of a part of the article to be formed, the other part being formed in an upper die to be presently described.

A link 50 is pivoted at 51 to a standard 52 on the lower frame member 15 and extends beneath the plunger 13 where it is provided with a loop portion 53. Pivotally mounted in this loop on trunnions 54 and 55 (FIGS. 4 and is a die carrier 56 of generally U-shaped form, open at the top. The ends of this member are closed by plates 57 and 58 (FIG. 3) secured in place by screws or the like 59 (FIG. 5). The lower portion of this member is reduced in size and this reduced portion 60 constitutes the upper die having the die opening 61 therein which is complemental to the opening 45 in the lower die. A bore 62 extends upwardly from the opening 61 through the bottom of the die carrier 56, and in this opening is mounted an ejecting or stripping sleeve 63 secured at the center of a bar 64 mounted for vertical movement in a slot 65 through the bottom portion of the die carrier 56. This bar and the sleeve 63 carried thereby is adapted to be engaged by pins 66 secured to a plate 67 (FIGS. 5 and 6), which plate is secured to a bracket 68 ladjustably attached to the cross bar 12 (FIG. 1). The plate 67 is provided with a cut-out portion 70 to permit the ram 28 and cylinder 34 to pass therethrough into the cup-shaped die carrier 56 as shown, for example, in FIGS. 3 and 4. It will be understood that the plate 67 is fixedly secured with respect to the frame so that when the upper die 60 is moved upwardly, as shown in FIG. 6, the pins 66 will engage the end portions of the bar '64 and cause relative movement between the sleeve 63 and the die 61 and thus eject the workpiece from the die if it tends to cling thereto. A plate 71 (FIG. 6) extends across the bottom of the carrier 56 and is secured thereto to limit upward movement of the bar 64, and this plate is provided with recesses 72 through which extend the pins 66.

The upper die in this instance is not moved by the ram 28 but its movement to and from a closed position shown in FIGS. 3 and 4 is effected by means of a cam 75 mounted on the cam shaft 48. This cam is provided with a cam track 76 in which rides a follow roller 77 rotatably mounted on a lever 78 pivoted to the frame at one end as at 79. One end of an adjustable link 80 is pivoted to the lever 78 at 81, and the other end of the link mechanism is pivoted at 82 to the link 50 to which is attached the die carrier 56. The cam track 76 is so shaped that it not only moves the upper die to a closed position, but also holds it in this position during the bulging of the workpiece.

In making a bulged article such as a sheet metal door knob, for example, the blank may be in the form of a disk-like member shown at 83 in FIG. 8. This member is first cupped, as shown at 84 in FIG. 9, and thereafter is drawn or necked, as shown at 85 in FIG. 10, where it Will be seen the body of the article is of substantially the same diameter as that in FIG. 9 but an upper reduced neck portion 86 has been drawn thereon. The above operations may be performed at a number of stations in the machine as required. Usually it will require more than one operation to form the necked cup shown in FIG. 10 from the straight-sided cup shown in FIG. 9. In the form shown in FIG. 10 the workpiece is now ready for the final bulging operation performed by the mechanism shown in FIGS. 2 to 7 inclusive.

With the plunger 13 and ram drawn upwardly, as shown in FIG. 6, so as to separate the dies 44 and 60, the blank 85 is introduced into the lower die. At this time it will be seen that the cylinder 34 is in its lowermost position on the ram 28, it being urged to this position against the shoulder 31 by the spring 37. The upper die 60 is then brought down on the neck of the workpiece, against the shoulder between the neck and the body, by the cam 75. The ram and cylinder are then moved downwardly until the nut 42 strikes the plate 71 which introduces the container bag into the workpiece. Continued movement of the ram 28 relatively to the cylinder serves to compress the spring 37 and move the ram downwardly in the cylinder 34, thus forcing liquid from the cylinder into the container 38 to build up pressure therein and prevent collapse of the blank during the closing of the dies. Thereafter movement of both the upper die and ram downwardly closes the two dies, as shown in FIGS. 3 and 4, and finally the ram moves downwardly to "a lower position in the cylinder 34 to further expand the bag or container 38 and force the metal of the workpiece outwardly into close contact With the sides of the opening formed between the die members 44 and 60. This is the final position of the parts and the resulting shape of the workpiece is shown at 87 in FIG. 11.

It will be apparent that during the foregoing operation the closing of the dies is effected by the cam 75 and, therefore, this closing movement of the dies is controlled independently of the movement of the plunger so that the dies can be closed at any time while permitting the plunger to continue its movement, although the closing is synchronized with the movement of the plunger. Such a construction is advantageous over one wherein the movable die is actuated by the movement of the plunger.

Continued rotation of the cam shaft 20 causes the cam 19 to lift the plunger 13 and ram 28 which first relieves compression on the spring 37 and thereafter raises the cyllnder 34 and the container 38, raising the latter out of the workpiece. The upper die 60 is moved to its upper position by the cam 75, thus raising the bar 64 of the stripper sleeve 63 until it is engaged by the pins 66, as shown in FIG. 6. This holds the stripping sleeve 63 against further upward movement and, as the die 61 1s moving upwardly, the work is ejected from the die. If the work clings to the lower die, it will be ejected by the ejecting rod 46 actuated by the cam 47.

It has been found that a bulged article can be produced by the present apparatus from a sheet metal blank by a continuous series of operations without interruption for annealing, and an article such as a door knob, for example, can be made economically and the resulting product will have the required strength and smoothness of finish and is made by a more economical method than has previously been employed.

It will be understood that while, as illustrated, the two die members are relatively movable in the same direction as that of the movement of the plunger, my method will also be employed in an apparatus wherein the dies may be split vertically instead of horizontally, as shown, and moved horizontally from open to closed position, such movement also being effected by cam means independen-tly of but synchronized with the movement of the plunger. Also, the positive closing or relative movement of the dies independently of the plunger may be effected when the blank is filled with free liquid and the plunger moved into the cup-shaped blank to hydraulically expand the walls thereof instead of employing an expansible bag or container for the liquid. In that event, however, a new supply of liquid would be introduced into the blank at each operation. Also the method and mechanism could be used with a deformable rubber plunger connected to the ram instead of employing the cylinder and watercontaining bag.

While I have shown and described one embodiment of my invention and a preferred apparatus of carrying out the disclosed process, it will be understood that the invention is not limited to all of the details shown but is capable of modification and variation within the spirit of the invention and within the scope of the claims.

What I claim is:

l. A press mechanism for bulging the walls of a cupshaped workpiece comprising a frame, a ram slidably mounted thereon, a fluid-containing cylinder slidably embracing the ram and carried thereby in fluid-tight relation with the ram, said ram projecting from one end of the cylinder, a pressure-fluid container of flexible material carried by and depending from the other end of the cylinder and having its open upper end secured in fluidtight relation to the cylinder and in communication with the interior thereof and closed at its lower end, means to retain the cylinder on the ram, a pair of relatively movable cooperating die members having die cavities which, when the members are in closed position, together form a die chamber of the shape of the finished article mounted in line with said ram, means for moving said ram relatively to the die members to introduce the container into the workpiece when the latter is positioned between the die members and apply pressure to the fluid in the container, and independent means for effecting relative movement of the die members to closed position in timed relation to the application of pressure in the container so that suflicient pressure is applied to the interior walls of the workpiece prior to closing of the dies to prevent collapse of the workpiece when the dies are closed and whereby continued movement of the ram expands the wall of the workpiece laterally into contact with the Wall of the die chamber.

2. A press mechanism for bulging the walls of a cupshaped workpiece comprising a frame, a ram slidably mounted thereon, a fluid-containing cylinder slidably embracing the ram and carried thereby in fluid-tight relation with the ram, said ram projecting from one end of the cylinder, a pressure-fluid container of flexible material carried by and depending from the other end of the cylinder and having its open upper end secured in fluidtight relation to the cylinder and in communication with the interior thereof and closed at its lower end, means to retain the cylinder on the ram, a pair of relatively movable cooperating die members having die cavities which, when the members are in closed position, together form a die chamber of the shape of the finished article mounted in line with said ram, means independent of the ram for eflEecting relative movement of the die members to closed position in timed relation to the movement of the mm, and means for moving the ram relatively to the die members to introduce the container into the workpiece when the latter is positioned between the open die members and move the cylinder against the adjacent die member to check movement of the cylinder whereby continued movement of the ram applies increasing pressure to the liquid in the container while the dies are independently closed on the workpiece.

References Cited in the file of this patent UNITED STATES PATENTS 1,348,892 Pierson Aug. 10, 1920 2,292,462 Milford Aug. 11, 1942 2,407,855 Stephens Sept. 17, 1946 2,688,297 Livermont et al Sept. 7, 1954 2,712,717 Keller July 12, 1955 ,761,405 Moller Sept. 4, 1956 2,821,945 Peccerill Feb. 4, 1958 

1. A PRESS MECHANISM FOR BULGING THE WALLS OF A CUPSHAPED WORKPIECE COMPRISING A FRAME, A RAM SLIDABLY MOUNTED THEREON, A FLUID-CONTAINING CYLINDER SLIDABLY EMBRACING THE RAM AND CARRIED THEREBY IN FLUID-TIGHT RELATION WITH THE RAM, SAID RAM PROJECTING FROM ONE END OF THE CYLINDER, A PRESSURE-FLUID CONTAINER OF FLEXIBLE MATERIAL CARRIED BY AND DEPENDING FROM THE OTHER END OF THE CYLINDER AND HAVING ITS OPEN UPPER END SECURED IN FLUIDTIGHT RELATION TO THE CYLINDER AND IN COMMUNICATION WITH THE INTERIOR THEREOF AND CLOSED AT ITS LOWER END, MEANS TO RETAIN THE CYLINDER ON THE RAM, A PAIR OF RELATIVELY MOVABLE COOPERATING DIE MEMBERS HAVING DIE CAVITIES WHICH, WHEN THE MEMBERS ARE IN CLOSED POSITION, TOGETHER FORM A DIE CHAMBER OF THE SHAPE OF THE FINISHED ARTICLE MOUNTED IN LINE WITH SAID RAM, MEANS FOR MOVING SAID RAM RELATIVELY TO THE DIE MEMBERS TO INTRODUCE THE CONTAINER 